CN112824684A

CN112824684A - Centrifugal pump impeller and noise reduction method thereof

Info

Publication number: CN112824684A
Application number: CN201911143540.4A
Authority: CN
Inventors: 程效锐; 李天鹏; 王鹏; 李敏; 蒋艺萌; 陈红杏
Original assignee: Lanzhou University of Technology
Current assignee: Lanzhou University of Technology
Priority date: 2019-11-20
Filing date: 2019-11-20
Publication date: 2021-05-21

Abstract

The invention discloses a centrifugal pump impeller and a noise reduction method thereof, comprising a mouth ring, a front cover plate, a blade working surface, a blade back surface, a rear cover plate, a gap and an impeller main body, and an outer wall of one side of the impeller main body is fixedly connected with a mouth A front cover plate and a rear cover plate are fixedly installed on the two outer walls of the impeller main body, respectively, and the two outer walls of the impeller main body are provided with a working surface of the blade and the back of the blade, and the outer walls of the working surface of the blade and the back of the blade are distributed with slits. ; The noise reduction method is to provide a new impeller structure to control the noise of the centrifugal pump. Slotting is performed on the trailing edge of each blade of the impeller, which can reduce the pressure difference between the working surface and the back of the blade, thereby reducing the The complex flow such as flow separation and wake at the blade outlet is optimized without affecting its performance and increasing the cost as much as possible, and it can be mass-produced. The slit design not only improves the life of the centrifugal pump, but also reduces the harm to the environment. .

Description

Centrifugal pump impeller and noise reduction method thereof

Technical Field

The invention relates to the technical field of single-stage and single-suction centrifugal pumps, in particular to a centrifugal pump impeller and a noise reduction method thereof.

Background

At present, pumps are widely applied to various industries, wherein about 70 percent of the pumps are centrifugal pumps, the centrifugal pumps are often accompanied by noise in the operation process, the noise becomes a very important problem along with the rapid development of the centrifugal pumps in recent years, and the source of the noise generation needs to be known to solve the noise of the centrifugal pumps; the noise of the centrifugal pump comprises mechanical noise and hydraulic noise, wherein the mechanical noise mainly comes from mechanical manufacturing and is controlled, and the mechanism of the fluid noise of the centrifugal pump is complex and is not completely solved, so that the noise of the centrifugal pump is the key point of current research;

in the operation process of the centrifugal pump, due to the fact that a strong dynamic and static interference effect exists between the impeller and the volute, complex flow field motion is easy to form, particularly, large flow separation is generated near the tail edge outlet of the blade, and further the formed wake flow-jet flow and the like further aggravate pressure fluctuation at the volute tongue partition, large fluid noise is caused, great influence is caused on the surrounding environment and physical and mental health of people, and meanwhile the service life of the centrifugal pump is shortened due to mechanical vibration and fatigue caused by severe pressure fluctuation.

Disclosure of Invention

The invention aims to provide a centrifugal pump impeller and a noise reduction method thereof, which aim to solve the problems in the background technology.

In order to solve the technical problems, the invention provides the following technical scheme: the utility model provides a centrifugal pump impeller, includes choma, front shroud, blade working face, the blade back, back shroud, gap and impeller main part, fixedly connected with choma on one side outer wall of impeller main part, fixed mounting has front shroud and back shroud on impeller main part's the both sides outer wall respectively, be provided with blade working face and the blade back on impeller main part's the both sides outer wall, the gap has been seted up in the distribution on the outer wall at blade working face and the blade back.

A noise reduction method for an impeller of a centrifugal pump comprises the following steps of manufacturing the impeller of the centrifugal pump; step two, opening blade gaps;

in the first step, the centrifugal pump impeller is molded by a casting mold according to the traditional process;

in the second step, the blade working surface and the blade back surface of the impeller manufactured and molded in the first step, which are close to the edge of the blade outlet, are subjected to slotting treatment, and each blade is provided with a slot.

According to the technical scheme, in the second step, the ratio Dk/D2 of the radial diameter Dk of the slot to the outer diameter D2 of the impeller body is n (n is 0.5-1), wherein an arc line perpendicular to each streamline in the drawing is made at the position of the rear cover plate Dk/D2 as a starting line of the slot; the ratio δ/b of the blade gap width δ (gap width is equally distributed along the start line) to the blade exit width b is 1/6.

According to the above technical scheme, in the second step, the impeller main body does not rotate along with the impeller blades in the fluid operation process, and a certain included angle β (β is a relative flow angle at the intersection point of the circular arc made by taking Dk as the diameter and the blade profile line) is formed between the impeller main body and the rotation direction of the impeller, and the selection of the angle β during slotting needs to be consistent with the relative flow angle of the fluid mass point at the slotting position.

Compared with the prior art, the invention has the following beneficial effects: the invention provides a brand-new impeller structure for controlling the noise of the centrifugal pump, and the rear edge of each blade of the impeller is slotted, so that the pressure difference between the working surface and the back surface of the blade can be reduced, the flow separation, wake flow and other complex flows at the outlet of the blade are further reduced, the slotted section is perpendicular to the blade of the impeller, the design optimization is carried out on the premise of not influencing the performance of the blade as much as possible and not increasing the cost, the mass production can be realized, the slotted design not only prolongs the service life of the centrifugal pump, but also reduces the harm to the environment.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic perspective view of an impeller for a centrifugal pump according to the present invention;

FIG. 2 is a slotted cross-sectional parameter schematic view of a centrifugal pump impeller blade according to the present invention;

FIG. 3 is a schematic representation of the movement of fluid in the vanes of a centrifugal pump impeller in accordance with the present invention;

FIG. 4 is a flow chart of the method of the present invention;

in the figure: 1. an oral ring; 2. a front cover plate; 3. a blade working face; 4. the back of the blade; 5. a rear cover plate; 6. a gap; 7. An impeller body.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-4, the present invention provides a technical solution: a centrifugal pump impeller comprises an orifice ring 1, a front cover plate 2, a blade working surface 3, a blade back surface 4, a back cover plate 5, a gap 6 and an impeller main body 7, wherein the orifice ring 1 is fixedly connected to the outer wall of one side of the impeller main body 7, the front cover plate 2 and the back cover plate 5 are fixedly installed on the outer walls of two sides of the impeller main body 7 respectively, the blade working surface 3 and the blade back surface 4 are arranged on the outer walls of two sides of the impeller main body 7, and the gap 6 is distributed on the outer walls of the blade working surface 3 and the blade back surface 4;

in the second step, slotting is carried out on the blade working surface 3 and the blade back surface 4 of the molded impeller close to the edge of the blade outlet in the first step, and each blade is provided with a slot 6; the ratio Dk/D2 of the radial diameter Dk of the gap 6 to the outer diameter D2 of the impeller body 7 is n (n is 0.5-1), wherein an arc line perpendicular to each streamline in the drawing is made at the position of the rear cover plate 5Dk/D2 which is n and is the starting line of the slot; 1/6 is the ratio/b of the width delta of the blade gap 6 (the width of the gap 6 is equally distributed along the starting line) to the width b of the blade outlet; the impeller main body 7 does not rotate along with the impeller blades in the fluid running process, and forms a certain included angle beta (beta is a relative flow angle at the intersection point of an arc and a blade profile line which take Dk as the diameter) with the rotating direction of the impeller, and the selection of the angle beta during slotting needs to be consistent with the relative flow angle of fluid particles at the slotting position; the impeller of the centrifugal pump and the noise reduction method thereof are characterized in that a blade working surface 3 and a blade back surface 4 of the impeller, which are close to the edge of a blade outlet, are slotted, and each blade is provided with a gap 6, the method is adopted for detailed design, as shown in figure 1, the impeller is a closed centrifugal impeller, and a working medium is liquid; the width δ of the gap 6 is b/6, the ratio Dk/D2 of the radial diameter Dk of the blade gap 6 to the outer diameter D of the impeller is n (n is 0.5-1), an arc line perpendicular to each flow line in fig. 2a is made at the position of the rear cover plate 5Dk/D2 which is n as the starting line of the slit, the slit is equally wide along the starting line, the slit angle is β, β is the relative flow angle at the intersection point of the arc made by taking Dk as the diameter and the blade profile line, and the specific details are shown in fig. 2 b; when the impeller rotates, as shown in fig. 3, a is a streamline of a fluid in the blade when the impeller is stationary, b is a track of a fixed particle motion on the blade when the impeller rotates, c is a streamline of an absolute motion of the fluid in the impeller, the fluid does not rotate along with the impeller blade in the actual operation process, and has a certain included angle with the rotation direction of the impeller, the selection of the angle β at the opening seam is consistent with a relative flow angle of the fluid particle at the opening seam position, and according to a velocity synthesis theorem, the relationship between the two is as follows: where c is the absolute movement velocity, w is the relative velocity, and u is the peripheral velocity.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a centrifugal pump impeller, includes choma (1), front shroud (2), blade working face (3), the blade back (4), back shroud (5), gap (6) and impeller main part (7), its characterized in that: fixedly connected with choma (1) on the outer wall of one side of impeller main part (7), fixed mounting has front shroud (2) and back shroud (5) respectively on the both sides outer wall of impeller main part (7), be provided with blade working face (3) and blade back (4) on the both sides outer wall of impeller main part (7), gap (6) have been seted up in the distribution on the outer wall of blade working face (3) and blade back (4).

2. A noise reduction method for an impeller of a centrifugal pump comprises the following steps of manufacturing the impeller of the centrifugal pump; step two, opening blade gaps; the method is characterized in that:

in the second step, the blade working surface (3) and the blade back surface (4) of the molded impeller close to the blade outlet side are subjected to slotting treatment in the first step, and each blade is provided with a gap (6).

3. A method of reducing noise in a centrifugal pump impeller according to claim 2, wherein: in the second step, the ratio Dk/D2 of the radial diameter Dk of the gap (6) to the outer diameter D2 of the impeller main body (7) is n (n is 0.5-1), wherein an arc line perpendicular to each streamline in the drawing is made at the position of the rear cover plate (5) Dk/D2 as an initial line of the slit; the ratio δ/b of the width δ of the blade gap (6) (the width of the gap (6) is uniformly distributed along the starting line) to the width b of the blade outlet is 1/6.

4. A method of reducing noise in a centrifugal pump impeller according to claim 2, wherein: in the second step, the impeller main body (7) does not rotate along with the impeller blades in the fluid operation process, and a certain included angle beta (beta is a relative flow angle at the intersection point of an arc made by taking Dk as the diameter and a blade profile) is formed between the impeller main body and the rotation direction of the impeller, and the selection of the angle beta during slotting needs to be consistent with the relative flow angle of fluid particles at the slotting position.